A broadband access may be implemented by a fiber optical access network, e.g. by a B-PON (Broadband Passive Optical Network or a G-PON (Gigabit-capable Passive Optical Network), and such a passive optical network (PON) does not use any electrically powered components to split the signal. A PON comprises an OLT (Optical Line Terminal) located at the service provider (operator), and the OLT provides an interface for the delivery of the services, e.g. telephony, Ethernet data or video over the PON. The PON typically also comprises one or more ONUs (Optical Network Units) or ONTs (Optical Network Terminations), which are connected to the OLT over an ODN (Optical Distribution Network), the ODN including optical fibers. Each ONT/ONU terminates the PON and converts the optical signals into electrical signals for delivery of the services to the end-user terminals, via a suitable user interface.
An ONU (Optical Network Unit), as mentioned above, is defined as a device that terminates any one of the distributed (leaf) endpoints of an ODN, implements a PON protocol, and adapts PON PDU (Protocol Data Units) to a subscriber service interface. An ONT (Optical Network Termination) is defined as a single subscriber device that terminates any one of the distributed (leaf) endpoints of an ODN, implements a PON protocol, and adapts PON PDUs to a subscriber service interface. An ONT may be further provided e.g. with an Integrated Residential Gateway.
Hereinafter, the generic term ONT refers to an ONU or an ONT.
The ONT Management and Control Interface (OMCI) protocol is a standardized PON-management protocol that defines the properties of different Managed Entities, MEs, i.e. units or parts of a passive optical network, and a Managed Entity comprises a number of configuration parameters. The configuration of the ONT is performed via the OLT, using the OMCI protocol, and the configuration parameters are stored in an OMCI MIB (OMCI Management Information Base).
The CWMP (CPE WAN Management Protocol), i.e. the Customer-Premises Equipment Wireless Access Network Management Protocol, is another standardized PON management protocol that is defined by the Broadband Forum, and the CWMP may e.g. be used for managing the functions of a residential gateway.
Conventionally, an ONT is managed by the above-mentioned OMCI, and all functions of the ONT are managed only by this management protocol. However, a more advanced ONT is able to integrate e.g. a residential gateway functionality, wherein the typical PON-related functions are managed through the OMCI, and the residential gateway functions are managed e.g. by the above-mentioned CWMP. Thus, multiple management protocols and data models, i.e. multiple management domains, can be used for managing an integrated ONT, wherein the ONT may be provided e.g. with an integrated residential gateway functionality.
Today, an ONT can be manufactured with a size that is small enough to fit into e.g. an SFP (Small Form-factor Pluggable), and an SFP provided with an ONT may be plugged into any kind of host device that requires PON access, e.g. into a radio base station, a home gateway or an Ethernet switch.
However, in case an ONT is connected to a host device that is managed by a different management protocol than the OMCI, the management protocol of the host device has to be able to interact with the OMCI of the ONT. The host device could be managed e.g. by the SNMP (Simple Network Management Protocol), by the above-mentioned CWMP or by Telnet, and the host device could be managed by any management server used by the customer.
Thus, the host device has to know the basic access-related configuration and capabilities of the ONT, e.g. QoS parameters, bandwidth allocations, scheduling and optical information, in order to interact with the ONT. The host device may also have to send OMCI configuration-related information back to the ONT.